Teletypewriter switchboard



Sept. 24,1946. P. v. KOOS TELETYPEWRITER SWITCHBOARD Filed April 50,1943 6 Sheets-Sheet 2 lNl/ENTOR P. l/f xoqs 5V 3. 5.

ATTORNEV Sept. 24, 1946.

P. V. KOOS TELETYPEWRITER SWITCHBOARD Filed April so, 1945 6Sheets-Sheet 5' v INVENTOR P.-V.'KO 0$ ATTORNEY p P. v. Koos 2,408,074

- TELETYPEWRITER SWITCHBOARD Filed April so, 194: s sheets sheet 4 INVENT OR P. v. KOQS ATTORNEY Sept. 24,1946. P. v. K0 5 4 01TELETYPEWRITER SWITCHBOARD Filed A r 11 so, i194: e Sheets-Sheet s l/V,VE N TOR P. wroqs ATTORNEY 6 Sheets-Sheet 6 FIG. 6

//v VENTOR P. 1 K005 BY J a P. v. KOOS I TELETYPEWRITER SWITCHBOARDFiled April 30, 1943 Sept. 24, 1946.

///417I////7////z ,7/////,7//////////////4'/7/////////A'm Patented Sept.24, 1946 UNITED STATE s PATENT OFFICE TELETYPEWRITER SWITCHBOABD Paul V.Koos, Manhasset, N. Y.,'assignor to Bell Telephone Laboratories,

Incorporated, New

York, N. Y., a corporationof New York I i 7 Application April 30, 1943,Serial No. 485,136

v This application continues subject-matter disclosed and claimed in mycopending application Serial No. 302,837, filed November 4, 1939, andthe benefit of the filing date of that application is claimed for allpurposes under'whatever pro- An object of the invention is theimprovement of communication switchboards.

A more particular object of the invention is the improvement ofteletypewriter switchboards. Since the lntroducti'on'into thecommunication industry of teletypewriter switching systems, considerableeffort has been expended toward evolving a desirable teletypewriterswitchboard. The satisfactory disposition of the teletypewriterinstrument'itself with respect to the switchboard is a'problem which haslong engaged the attention of inventors and designers.

One of the principal difiiculties encountered was the excessive amountof'space required by the teletypewriter. As i well known by thosefamiliar with the art, a teletypewriter is a piece of apparatus whichrequires considerable mountmg space. of an operator which is availablefor jacks, etc. A number of solutions were suggested, none of which wasentirely satisfactory. When the teletypewriters are mounted, as theysometimes are, on movable tables below the switchboard operating shelf,the level of the operating shelf must be in an elevated position toprovide both for the height of the teletypewriter and a kneewell for theoperator below the teletypewriter table. Further, this limits the heightof the jack field which an operator can reach. There is another seriousobjection to this arrangement in that the tablelegs supporting theplatform on which the teletypewriter is mounted become -obstructions,limiting movement beneath the key-shelf.

Heretofore in the case of manually operated teletypewriter switchboardsin which cords and plugs were used in establishing connections and whichincluded jack pile-ups with their openings arranged in a vertical bank,wherever plug-ended communication cards have been mounted above ateletypewriter in the same vertical tier, the plugs have been mountedinna plug-shelf which This reduces the space within reach 17 Claims.(01'. 178 75) projected in front of the vertical face of the board. Theplug-shelves have generally been horizontal, but in some designs theyhave been inclined upwardly toward the jack field in the vertical faceofthe board." In both of these arrangements wherever'teletypewriters havebeen 7 located in the same vertical tier in which plugendedcommunication cords and a jack field were also located, so as to provideall of the essential operating equipment used in establishinginterconnections in the same single operatorgposition, theteletypewriter has been mounted on a separate table which hasbeen'arranged'to be moved into position under the plug-shelf.

As a result 'of mounting the teletypewriter on a table and locating itbeneath the plug-shelf,

vertical space in the board was required to accommodatetheteletypewriter, the plug-shelf and the protruding plugs. 'Anoperator'seated before the board in front of the teletypewriter had toreach over the plug-shelf in making connections of the jack field. Thisadversely affected operation in two ways. First, it reduced the areaavailable for jacks within reach of the operator. Second, it slowed upoperation of the board as the jack field was so far removed from theoperator. Both of these adverse factors, in turn, made it necessarywhere such arrangements were used in large teletypewriter centralswitching stations to provide more switchboard positions and moreoperators to handle a given load than would be the case if it werepossible to eliminate the protruding plug-shelf.

The operating difficulties presented by the! necessity for providingplug-ended cords mounted on a plug-shelf, a teletypewriter and avertical bank of jacks, all in the same operating position in ateletypewriter switchboard have been accepted as inescapable by theindustry. Theupper portion of a modern communication switchboard isdevoted almost entirely to the accommodation of a vertical jack bank andthe cabling and wiring of the jack bank. In such switchboards the spacein the rear of the jacks is literally full of this cabling and wiring.The jack field in the front of the upper portion of the board and thecabling and wiring serving the jack field behind the jacks both extendfrom a level a little above the top of the plugs in the lplug-shelf to aheight determined by the limits 7 of an average operators reach.

i It has heretofore always been accepted in the communications industrythat there were buttwo munication switchboards having vertical jackbanks, namely, below the jack field or above the jack field, and that ofthese two possible positions only the one below the jack field, wherethe cords and plugs have heretofore almost invariably been located, hasbeen considered feasible. There are a number of reasons for this. First,it is necessary to provide sufiicient slack in the cords so thatconnections may be made. Space must, therefore, be provided for theslack. The slack obviously cannot hang down in the space among the jackcabling and wiring which completely fill the space immediately behindthe jack field. So it was heretofore considered impossible to locate theplugs and cords in such a manner that the cords hung down behind thejacks.

Plugs have hereto-fore been located above a jack field in certain of theoldest telephone boards which were operated by operators standing be-:fore the board. Where this has been done, the cords have been extendedupwardly above the switchboard and run through sheaves attached to anopen superstructure above the switchboard to prevent interference withthe jack cabling and wiring. Plugs have also been located at the top oftrouble positions, etc., and cords have been permitted to dependdirectly from plugs so located in positions in which there was no jackwiring. It would not be practical to arrange the plugs and cords used.in establishing connections between subscribers in a modern switchboardin this manner or in any manner which involved locating the plugs, usedin extending circuits be tween stations, at the top of the board, as anoperator seated before the board would be required to reach above thetop of the jack field for a plug on making each connection and such operation would be too slow.

Communication plugs and cords in all modern manual switchboards operatedby an operator seated before the board, which switchboards include avertical jack field, therefore, have heretofore been located below thejacks and the jack wiring. The plugs, as heretofore explained, arearranged to protrude through a shelf which is generally horizontal butwhich at times is arranged t incline upwardl toward the jack field. Inall cases the shelf has been located beneath the jack field. The cordshung down from the plug, seated in the plug-shelf, passing throughmovable weighted sheaves or cord weights which serve to withdraw theplug and reseat it in the plug-shelf when it is released after use bythe operator. The rear end of the cord is attached to a cord-shelf whereits flexible conductors are terminated for interconnection to the relayand signaling equipment. The cord-shelf has been mounted heretoforebehind the plug-shelf in a fixed position at approximately the samelevel as the plug-shelf.

The space in the modern manual cord operated communication switchboardimmediately behind the operators kneewell is almost entirely reservedfor the cords and cord weights. The cord weights serve not only towithdraw the cords after disconnection but alsoto maintain the cordsreasonably taut and to keep the tangling of the cords to a minimum. Dueto the slapping about of the cord weights, particularly when cords arebeing Withdrawn by the weights, it is not possible to mount anyequipment in the space reserved for the cord slack. No other electricalequipment is mounted in this space as it would be susceptible to injuryand would tend to indevised.

crease tangling. Even when the space reserved for the slack is keptcompletely free of equipment, it is not possible to completely eliminatecord tangling which is still a serious problem arising most frequentlywhen adjacent cords are being withdrawn simultaneously.

Because of these and other considerations, from the time when'teletypewriter switchboards were first designed up to the present time,the cords were located in their usual position below the jack field. Noentirely satisfactory manner of accommodating a vertical jack field, ateletypewriter and cords in the same vertical tier in a teletypewrlterswitchboard has heretofore been The difficulty was that the mostdesirable position for the. location of the teletypewriter wasimmediately below the vertical jack bank. The plug-shelf, plugs andcords occupied this position. Locating the plug-shelf between the jackfield and the teletypewriter was wasteful of available jack space withinreach of an operator and resulted in a reduced number of availablejacks.

In certain teletypewriter switchboard designs the teletypewriter wasmounted on a horizontal shelf in the switchboard to one side or theother of the plug-shelf. As a result of this an operator seated in thenormal operating position in front of the teletypewriter had to reachover to the right or left to an adjoining plug-shelf to obtain a cord inmaking a connection which, of course, slowed up operation. Otherarrangements included mounting the teletypewriter on tables in such aposition that the teletypewriter keyboard was at right angles to theface of the switchboard and there have been designs in which theteletypewriter was located on a table in front of and parallel to theface of the switchboard and spaced from the switchboard so that anoperator turned her back to the board when operating the teletypewriter.The disadvantage of such operation is obvious.

Manual teletypewriter switchboards as a result have been slow inoperation. This, as heretofore mentioned, has increased th number ofoperators and operating switchboard positions required to handle a givenload, which is reflected in the cost of the service. In conjunction withother factors, such as the necessity of an interchange of teletypedcommunication between the various switching points when establishingconnections, the relatively much slower rate of establishing connectionsin a manual teletypewriter system than in manual telephone systems hasgiven impetus to the development of the much more expensive mechanicalteletypewriter switching systems while investment in such expensivesystems is economically hazardous considering the relatively smalldemand for teletypewriter switching service.

The invention herein solves the problem of the mounting of atele'typewriter and plug-ended cords together with a vertical jack bankin the same vertical tier in a teletypewriter switchboard in a mannerwhich ('1) eliminates the plug-shelf in front of the board, (2)increases the number of jacks within'reach of an operator seated beforethe board, (3) prevents mechanical interference between theteletypewriter, the jack wiring and the cords and cord weights, (4)increases the number of connections which it is possible to handle in agiven time and (5) reduces the work expended in operating the board to aminimum.

One of the most important aspects of the invention, is a new design ofteletypewriter switchthat the top of the teletypewriter is in closeproximity with the bottom of the vertical jack pile-up and theplug-ended cords are arranged so that the plugs protrude horizontallythrough openings approximately in the middle of the space ordinarilyreserved for jacks and within short reach of the operator and the cordsand cord weights are arranged so that there 'is no interference betweenthe cords and cord Weights and either the wiring and cabling which servethe jacks or the teletypewriter, the rear of which is let into the boardimmediately below thejack wiring.

One of the important features of the invention is the arrangement ofcords and plugs, a vertical jack bank and a 'teletypewriter in the samevertical tier in a manner which effects the elimination' of a plug-shelfprojecting in front of the vided when the jack bank, the teletypewriterand the cord plugs have been arranged in the same verticalline-up'hasbeen eliminated, Notwithstanding the elimination of the separate cordplug-shelf projecting before the board, the cord plugs aslocated intheir present position are easily'accessible to an operator seatedbefore the board. Both the teletypewriter and aseparate co'rdplug-shelfare not interposed between the operator and the lowest jack level. Thenumber of jacks brought within the reach of the teletype writer operatorseated before the teletypewriter is greater than in any other design inwhich a "jack field; a teletypewriter and cord plugs are available inthe same vertical tier, due to the saving of the spaceheretoforerequired for the cord plug-shelf and. for clearance between the cordsand the teletypewriter.

In the present invention the cords and plugs are arranged so that theplugs protrude horizontally through openings in the vertical face of theswitchboard, between the same vertical stiles in which the jack bank issecured. The cord arrangement is such that the plugs may be mounted atany level in the space between the vertical jack stiles and the level ofthe cordshelf to which the cords are connected in the rear of the boardmay be adjusted to correspond to the level of the plugs. A secondimportant 'featureof the invention, therefore, is a plug and cordassembly which is adjustable in height.

There are a number of advantages to be derived from mounting the plugsat about the middle'level'of the jack field to which connection is made.this invention, therefore, is in the middle of the jack field which theyserve. But the invention is not limited to the location of the plugs inthe middle of the jack field. Since the cord-shelf is adjustable inheight and the plugs may be located at any level in the board thesefacilities may be mounted at any desired level in the board. The plugsmay be arranged toprotrude horizontally through openings immediatelyabove the teletypewriter and below the jack field. In all The preferredlocation of the plugs per positions the cord weights .are arranged sothat they cannot strikethe teletypewriter and so that the teletypewriterand cords do not interfere. 'If

the plugs are located in the space between the bottom of the jacks andthe top of the teletypewriter. instead of in the preferred location inthe middle of the jack field space, however, a number of the importantadvantages to be derived from the invention in speed and convenience ofoperation and in reduced first cost and maintenance expense to bedescribed hereunder are sacrificed. j

Attention is called to the fact that to establish each connection bymeans of a cord in a manual switchboard of any kind requires theperformance of work by the operator. It isnecessary to raise a certainlength of cord through a certain height. It is necessary to raise a cordweight through a certain height. It is also necessary toof connectionsestablished by an operator in a given time. 7

One of the important aspects of the invention herein is that the amountof workrequired to be performedin theoperation of the switchboard isreduced. This is attributableto the location of the plugs in the middleof the jack field in'the preferred arrangement.

In the ordinary manual cord operated switchboard the plugs are locatedbelow the jack field. If it is assumed that the average connection ismade to a jack in the center of the jack field, it is necessary as anapproximation to raise a length of cord equal to one-half the height ofthe jack field through a distance equal to onehalf the height of thejack field. It is necessary to raise a cord weight through one-half ofthis distance or one-quarter the height of the jack field. When theplugs are located in the center of the jack field, if it is assumed thatthe average connection is made to a jack in the middle of g the upperhalf of the jack field, it isnecessary to raise a length of cord equalto one-quarter the height of the jack field through a distance equal toa quarter the height of the jack field. Further, it is necessary toraise the cord weight through a distance equal to only one-eighth theheight of the jack field. In making connections to the lower half of thejack bank the work involved is" somewhat less than in making connectionsto the upper half due to the fact that the weight of the withdrawn cordis tending to aid the operation. As a result of this, the work involvedin lifting the weight of the cord and cord weight in the new preferredembodiment of the cords and plugs per the invention herein is reduced toless than half of that required in performing corresponding operationsin the ordinary switchboard. y

Another important feature of the invention herein, therefore, is thatthe cord and plug arrangement of the invention herein halves thephysical labor of operating the cords of a manual switchboard. Attentionis called to, the fact that although the cord and plug arrangement oftheinvention herein is particularly, efficacious in the case ofteletypewriter switchboards inthat it eliminates the separate plug-shelfwhich was formerly required in addition to the teletypewriter shelf andprevents mechanical interference between the cord weights and theteletypewriter, the rear of which can now be let into the switchboardfor a considerable distance, the cord and plug arrangement is notlimited to teletypewriter switchboards, but may be used to advantage inall switchboards employing cords and plugs in establishing connections.It may be used to advantage, for instance, in telephone switchboardswhere it will doubtless have its widest field of application.

There is another important aspect of the invention. One of the majordifficulties encountered in the operation of manual cord operatedswitchboards is caused by the fact that cords connected to jacks coverthe openings in other jacks and interfere with new connections. At times'in all switchboards a considerable number of the cords will beconnected to jacks. When the plugs are mounted at the bottom'of theentire jack field, their attached cords will, when connected, inevitablycover the openings of large numbers of jacks and interfere withconnections to these and to large numbers of others. Under certainconditions the diificulty is increased, for example, when a cord isalready connected to a jack at a position close to, but not quite at,the limit of the operators reach to the left or right and anotherconnection must be made to a jack located beyond the cord alreadyconnected; or when two or more cords are connected to closely spacedjacks and another connection must be made to a jack in the area betweenthe hanging cords. Not only is the difficulty of making connections andthe time required to make connections increased, due to the greaterlength of cord required in switchboards having cords arranged asheretofore, but also the longer cords obscure the operators'vision to alarger extent and cover the numbering of a larger number of jacks.Further, they cover the signal lamps. As a result of this, connectionsto jacks obscured by connected cords are not infrequently madeunconsciously by estimate and approximation and not infrequentlyerroneously, particularly by inexperienced operators. This affects notonly the patron, but the time required to correct the er-.

ror reduces the effective operating load which can be handled per unitof time and represents a considerable total loss in the aggregate.

Obviously the longer the cord required in making connections the greaterthe difficulty. Any rearrangement of the relationship of cords and plugsto the jack field which effects a reduction in the length of cordrequired in establishing connections minimizes these disadvantages. Theinvention herein, due to the new relationship which it establishesbetween the cords and the jacks, effects the maximum possible reductionin these difiiculties.

Another feature of the invention herein, therefore, is that theoperating difficulty caused by long lengths of operating cords hangingdown in front of the jacks in the jack bank is minimized due to theshorter length of cord required in establishing a connection when thecord plugs are located in the middle of the jack field.

As a result of devising the new cord arrangement of the invention hereinin which cords are carried back horizontally from the rear of the plugsto which they are attached between the layers of jack cabling and wiringuntil they clear the cabling and wiring and then drawing the cords overhorizontal bars of circular section arranged parallel to the face of thejack field, before permitting the cord slack to depend behind thecabling under the influence of the cord weight, an added advantage ofthe invention herein is obtainable which will now be particularlypointed out.

In the former arrangement of cords in manual switchboards where thecords were located below a jack field and where teletypewriters werelocated below the plugs, it was necessary to provide space immediatelybelow the plugs for the cords attached to the plugs. This was thecontrolling factor in the disposition of the teletypewriter instrumentin such switchboards. The teletypewriter wherever it has been located inthe same vertical tier with cord plugs has been located on a separatetable below the plugs and in front of the cords depending from theplugs. The table has been completely independent of the switchboard. Theteletypewriter could not be let into an obviously very desirable spaceimmediately below the plug shelf since the space formerly had to bereserved exclusively for the cords and cord weights. Mechanicalinterference between these elements could not be permitted for obviousreasons.

The improved cord arrangement per the invention herein permits the rearof the teletypewriter to be let into the board for a considerabledistance. This permits the operator to sit closer'to the board. Theshelf on which'the teletypewriter is mounted is depressed in the rear toeffect an increase of approximately three inches in, the vertical jackfield space within reach of the operator.

The elimination of the plug-shelf with the plugs protruding upwardly,letting the rear of the teletypewriter into the space formerly reservedexclusively for the cords and depressin the teletypewriter shelf so thatthe higher rear portion of the teletypewriter fits into a depressedrecess behind the board have, in combination, increased the efiectiveradius of the jack field within reach of the operator so that the numberof jacks brought within the reach of the average operator seated beforethe board may be increased by approximately 15 per cent over the otherarrangements in which the teletypewriter is mounted on a separate tablebeneath the cord plug-shelf. And this has been effected whilesafeguarding the teletypewriter and the cabling and wiring from injurydue to their being struck by the cord weights which is impossible withthe new arrangement.

The new teletypewriter switchboard arranged according to th s inventionto eliminate the plugshelf may in small offices be used independentlywithout other supplementary switchboard positions. Further, in largeinstallations, line-ups 60 of such switchboards may be used in whicheach switchboard position is so arranged. In such arrangements noplug-shelves would appear in the switchboard line-up. Switchboards, bothtelephone and teletypewriter, employing the prin- 65 ciples of thisinvention may be used as originating boards, completing boards, tollboards, supervisory boards, maintenance boards, information boards andservice observing boards as well as for other purposes. Concentrationboards used 70 in telegraph services for establishing semi-permanentconcentration groups or networks of "facilities for businesses such asbrokerage and newspaper chains, etc. may .be so arranged. Further, thenew switchboard may be located so as 76 to abut against switchboards ofother types having'their cords arranged as heretofore. An'illustrationof such a situation would be the employ- There is another importantaspect of invention. herein.- In certain types of communicationswitchboards such as .in telegraph or teletype- I writer concentrationboards wherein lease concentrations are established which may remainunchanged for days or even weeks at a time, large numbers of cords arerequired since many of them remain in service indefinitely. It has beenthe practice heretofore for this type of serviceto employ patching.cords equipped at both ends with plugs. These patching cords werecompletely detached from the switchboard and hung insome'convenientposition when not in use. When they were used in making connections theplugs were inserted in the jacks in the face of the switchboard and theentire cord was suspended between the plugs in front of the jacks. Largenumbers of cords draped in front of the jack field obviously was adisadvantage.

Cords attached to plugs projecting through the middle of the jack fieldmay be used for this purpose. Where the number of cords required isverylarge and it is not convenient to arrange all of the required cordsin this mannenadditional cords may be attached to plugs in the samevertical tier, which plugs are mounted in a plug-shelf which projects infront of the board as formerly. The two sets of cords are arrangedaccording to the invention herein in the same vertical tier in suchmanner that there can be no interference between the cords in the twodifferent locations.

These and other features of the invention may be understood from thefollowingdescription when read with reference to the associateddrawings, in which:

Fig. 1 is a left-hand front perspective view of an e-xemplary embodimentof this invention comprisinga complete teletypewriter switchboard inwhich the teletypewriter is located immediately below the jack field,the cords and plugs project through openings in the middle of the jackfield and the plug shelf which has always heretofore projected in frontof the jack field is eliminated;

Fig. 2 is a left-hand side view of the switchboard per Fig. 1, partly insection, which discloses the manner in which the cords are arranged sothat they may be drawn through openings in the middle of the jack field,while interference between .both the cords and cord weights and theteletypewriter, which is let into the space ordinarily occupied by thecords, as well as'interference between both the cords and cord weightsand the jack wiring is prevented;

, Fig.3 is a left-hand rear perspective view the switchboard;

Fig. 4 is aloft-hand front perspective view'of an embodiment of theinvention applied to a 'se rvice in which a'very large number of cordsand special equipment such as meters are required such as in a combinedtelegraph lease concentration and testing board, and in which aninclined operating. shelf'projects in front of a position adjoinin the.new switchboard and abuts tion; 1'

"Fig". 5 is 'aZleft-hand rear perspective view .of the combinedarrangement; and

Fig, 6 is a left-side view, partly ih'section, of the arrangement ofthey embodiment per Fig. 4 showing two sets of cords, one setbeingarranged to be'drawn through an opening in the jack field and a secondset being arranged to be drawn through an opening in the inclined shelfprojecting in front of the switchboard.

Refer'now to Fig.

.znThe switchboard I00 comprises essentially a framework. IOI,preferably of steel and a casing I02 preferably of wood. Secured to theupper front of the framework are vertical stiles I03, I04 and] 05.Between the vertical stiles are openings in which are secured fourvertical pile-ups of jack strips I06, I01, I08 and I09 arranged so thattheir jack openings form a vertical jack bank or. jack field. It ispointed out that lamp strips-may be included with the jack strips forcertain services, to be explained below. The-two upper jack pile-ups I06and I08 are spaced from the two lower jack pile-ups I01 and I09,respectively. In the opening between jack pile-ups I06 and IE1? are tworows .of cord plugs H0 and III, a strip of keys H2 and two strips oflamps II3. In the opening between jack pile-ups I08 and I09 are two rowsof cord plugs H4 and H5, a strip of keys H6 and two strips of lamps I".

It is particularly pointed out that the association of keys and lampswith the cord plugs is characteristic of cord circuit equipment such asis used, forv instance, in an originating board or what is known in theart as an A board in which one of a pair of cords would be employed inresponding to an incoming call, and another of the 7 pair in extendingthe call either to a subscribers each. plug and cord would be used toterminate atrunk circuit incoming from a distant switchboard and thekeys would generally be omitted. In such a case, no subscribersanswering jacks or lamps would be required and the jacks would be usedfor completing calls to the subscriber only. And in general, it is to beunderstood that the cords and plugs of the invention herein may serveany purpose for which such apparatus is employed in the communicationsindustry. And the operating apparatus with which the cords and plugs isassociated will vary to suit the special conditions. The greatestadvantage in the matter of additional jack space placed within reach ofthe operator will be achieved in the case of boards in which nooperating keys are required. In such case, the only operating equipmentrequired to be mounted in the. vertical face of the board in addition toplugs, other than the multiple jacks, would be either one or two stripsof lamps in each vertical panel which would require not more than oneinch of vertical space.

t the bottom of the jack panels and immediately above the teletypewriterI8 are pilingrails H0 and I 20. The teletypewriter H8 is mounted on ashelf immediately below the jack panels.

As maybe seen bestin Figs. 2 and 3 the teletypewriter H8 is mounted on ashelf us which is supported ona pair of bars I20 and I2I. ,Bar

[21! is welded to vertical frame members I22, I23 and IM and bar I2I iswelded to corresponding members. The shelf and bars are inclineddownwardly from the front toward the rear. This permits the rear portionof the teletypewriter which is higher than the front to be depressedbehind its front portion, and pushed behind the jack field as indicatedto effect a saving in the vertical space taken up by the teletypewriterin the plane of the .jack field.

The space immediately in the rear of the jack bank is ordinarilyoccupied exclusively by the cabling and wiring serving the jacks.Reference to Figs. 2 and 3 discloses the manner in which the cords andjack wiring have been rearranged per this. invention to permit the plugsto be located in the middle of the jack field and to permitthe/teletypewriter to be located in the space ordinarily occupied by thecord plugs and cords while at the same time preventing mechanicalinterference, between these elements and consequent damage therefrom.

A cord-shelf I25 is secured at each end to the rear of transverse barssuch as I26. Secured to the forward ends of each of the bars is a rightangle bracket such as I21. The depending vertical arm of the bracketssuch as I21 is drilled so they may besecured to vertical frame membersE23 and E23. A row of tapped holes extends along the edges of thevertical frame members I23 and I28 to engage with the drillings in thebrackets such as I21 to permit the cord shelf assembly to be mounted atany desired height in the board.

It is particularly pointed out that although in the: preferredarrangement the plugs protrude through an Opening in the middle of thejack field, the number of jacks whichare mounted in the jack field spacewill vary in different boards and at. different times in the same board.As is well known, a board may have relatively few jacks when it is firstput into service. The small number of. jacks initially required isinvariably mountedin the lower part of the jack space. Under suchcircumstances the cord-shelf assembly and the plugs will be lowered totake advantage of this condition. the recommended position for thecord-shelf assembly is in the middle of the jack field space. And forcertain operating conditions in certain special positions where speedand. convenience of. operation are not of importance, such as in thelocation of trouble cords, that is, cords which are employed to place atone condition on the sleeve, for instance, of a jack connected to aline in trouble, to provide an indication of the trouble condition whenan operator connects to a multiple appearance of the jack at anadjoining position, it will be convenient to locate the cord-shelfassembly at the topof the jack field space above the jacks.

Welded to each of the transverse bars such as I25, intermediate the endsof each bar is a vertically depending bar such as I37. Secured betweenthe vertical bars in. any convenient manner near the tops thereof anddisposed so that they are horizontal and parallel to the jack field andspaced one from another in vertical alignment are two rods I29 and I30of circular section. The bars are spaced vertically to correspond to thevertical spacing of the plugs H and III in the face of the board. Thecords I35 and I36 are arranged so that they extend from the plugs towhich they are attached horizontally to the rear passing over the topsof the circular rods When the jack space is full its respectivecircularrod, each cord passing through an individual weighted sheave or cordweight, after which the rear end of each cord is. attached to a cordhook such. as I3 I and the. cord. conductors are attached to individualterminals I32 all secured to the cordshelf: I26. Extending between thevertical depending bars such as I31 and secured to them in anyconvenient manner is bailie board I33. The arrangement of the cordsthemselves together with the interposition of the baffle board I33between the cord weights and the wiring and. other apparatus providesam-- ple protection againstv injury due to the swinging of the cordweights.

Reference to Fig. 2 discloses, as mentioned heretofore, that with thecords arranged as shown in this figure the length of cord which it isnecessary to draw through the opening in order to make connections willon an average be less than is required when the plugs are located in a:shelf projecting in front of the switchboard below the jack field. Thework which must, therefore, be performed in operating the board will inthe aggregate be less. Further, the elimination of the plug-shelfprojecting in front of the board above the teletypewriter permits theoperator to reach over a greater area of jack field while seated beforethe switchboard. The lengths of cord draped. in front of the jacks willbeon an average shorter. There will obviously be less interferencebetween cords already connected and cords in process of being connected.In short, the new arrangement disclosed in Figs. 1, 2 and 3 provides amanually operated teletypewriter switchboard in which the essentialelements; are so disposed that they cooperateto permit theinterconnection of more circuits and at faster rate and with theexpenditure of less physical energy than in any previously knownteletypewriter switchboard.

Refer to Figs. 4, 5 and 6. Fig. 4 shows an arrangement in which the newswitchboard disclosed in Figs. 1, 2 and 3 abuts against an adjoiningswitchboard on the left of a special type,

5 such as a testing board, wherein special apparatus such as meters isrequired as well as a considerable number of special plug-ended testingcords such that the aggregate, number of cords is more than can beconveniently accommodated 5 in the upper portion of the board in themanner heretofore described and the single teletypewriter in theright-hand portion of the combined switchboards is adequate for thecombined boards.

In this arrangement, advantage is taken of the vertical height taken upby the teletypewriter in the right-hand position in that the shelf 200of the special board in the left-hand position is inclined upwardly sothat its vertical rise is equal to the vertical height of theteletypewriter in the plane of the jack field. As thus arranged themeters will be approximately normal to the line of vision of theoperator. Further, the plugs 2M are raised as close to the bottom of thjack field as possible, so that the physical effort of raising thespecial cords is minimized.

Reference to Fig. 6 discloses the relative positions of the two sets ofcords in this arrangement. The arrangement of the upper set of cords isthe same as heretofore described. The rear end of each of the lower-setof cords is attached to a second cord-shelf 262 which is secured in afixed position between vertical frame members such as 203. This permitsa considerable increase in the number of cords which can 13 be locatedina 'switchboardfposition within con venient reach of an Operatorseated. before the switchboard. The spacing of the cords preventsinterference between them. 'This' obviates a difficulty previouslyencountered When theflloca tion of a, large number of cords in aposition within convenient reach of an operator was attempted.

What is claimed is:

l. Ina communicationsswitchboard, a cord having a plug attached thereto,vertical stile strips having openings therebetween, a displaceable plugseat for positioning said plug when in the normal idle disengagedcondition at'various levels in said openings, a cord-shelf, means forattaching one end of said cord to said shelf, and means for positioningsaid shelf at various levels dependent upon the level at which said plugis positioned.

- 2. In combination in a manual teletypewriter switchboard, a,communications conductor plug ended switching cord fastened at one endto a cord-shelf in the rear, of said switchboard and arranged toprojectfthrough a plug'support in the front of said board, means fordisplacing said support and means for displacing said shelf toaccommodate the displacement of said support.

3. In combination in a communications switchboard, a plug seat, a cordshelf, a communications cord having a first and a second end, aswitching plug attached to said first end, said second end attached tosaid shelf, said plug supported in said seat, said cord adapted to bedrawn through said seat to the front of said switchboard, means in saidswitchboard for'positioning said seat at various levels in saidswitchboard and means in said switchboard for positioning said cordshelf at various levels in said switchboard to correspond with theposition of said seat.

4. In a communications switchboard, 'a vertical jack bank, jack wiringbehind said bank connected to said bank, an opening forming a plug seatin substantial vertical alignment with jacks in said bank below saidopening in said bank, a plug protruding through said opening, acommunication cord having one end connected to said plug and extendingfrom said plug rearwardly directly horizontally between said wiring to apoint behind said wiring, and means, comprising a cord weight dependingfrom said cord, for introducing cord slack behind said point.

5. In a manual teletypewriter switchboard, a

I vertical jack field, wiring connected to the rear of jacks in saidfield, a communications cord connected at a first end to a cord-shelflocated behind said wiring intermediate the top and bottom of saidfield, said shelf in substantial horizontal alignment with an opening insaid field, a plug having a first end projecting through said opening infront of said field and a second end connected to a second end of saidcord.

6. A manual ,teletypewriter switchboard, a vertical jack; bank in'saidswitchboard, a plug attached to a cord in the rear of said jack bank,said plug projecting in front of said jack bank through a horizontalopening between said jacks in said bank, said opening separating saidjack bank into two portions one above the other in vertical alignment,jack wiring behind said bank connected to said jacks, an opening in saidwiring, a first support means for said cord comprising an elementimmediately behind said wiring, a second support means for said cordcomprising a cord shelf behind said element, slack in said corddepending behind said wiring between said first and said second supportmeans, said support means cooperating to adapt said cord so that it maybe drawn through said opening for connection to jacks in either'of saidjack field portions, to minimize the length of cord draped in front'ofsaid switchboard to reduce interference with other connections. 1

7 A manual teletypewriter switchboard, a communications'cord attached atone end to a plug, a vertical jack bank in the upper portion of saidswitchboard, jack wiring connected to the rear of jacks in said bank, ahorizontal opening in said bank between horizontal layers of said jacks,means for mounting said plug in said opening, and means for arrangingslackin said cord behind said wiring so that said cord may be drawnthrough said opening for connection to said jacks from the front of saidswitchboard without interfering .with said wiring.

8. In a manual cord communications switchboard, a vertical jack fieldhaving separate jack,

7 sections one above the other in the same vertical tier, an openingbetween said sections, cables behind said bank connected to th rearofjacks in each of said sections, an opening between said cables inalignment with said opening between said'sections, a communicationscord, supports. for said cord so that. said cord may be drawn" throughsaid opening between said cables and said sections for connectionto'jacks in either section to reduce the labor of operating saidswitchboard. I

9. In a manual teletypewriter switchboard, horizontal layers of jacksarranged to form a vertical jack field, a cord having a first endconnected to a horizontal cord shelf behind said jack field, said shelfmounted intermediate the top and bottom of said jack field, said cordhaving a second end arranged to extend through an opening betweensuccessive horizontal layers'of jacks in said field.

10. In a teletypewriter switchboard, a vertical jack field, wiringconnected to jacks in said field,

an opening in said field, said opening separating said jack field intotwo portions one'above the other, a plug ended switching cord attachedat one end to a horizontal cord shelf behind said wiring, said cordextending through a cord weight attached to said cord and means forsupporting said cord so that said cord may be drawn through.

said opening between said portions without interfering with said wiring,so that Saidplug may be connected to a jack in either of said portions,to minimize the length of cord draped in front of said jack field.

11. In a manual cord teletypewriter switch board, a plurality of jackssecured in jack strips,

a plurality of said strips piled in horizontal layers to form a verticaljack bank, a vertical opening in said bank separating said bank intovertical sections one above the other, cord support means in saidopening, a flexible switching cord adapted to be drawn through saidsupport, and a'plug connected to said cord, for establishingconnectionsthrough said cord to any of said jacks in either of said sections, so asto minimize the length of cord draped in front of said sections whenconnections are established between said cord and any one of said jacksto reduce interference when connections are established between othercords in said switchboard and other jacks in said bank. 12. In a manual,cord operated teletypewriter switchboard, a vertical jack bank, wiringconnected to the jacks in said bank behind said bank, a plug endedcommunications switching cord, a teletypewriter, means for supportingsaid teletypewriter immediately below said jack bank, an opening in saidbank above said teletypewriter and in vertical alignment with saidteletypewriter, means for arranging slack in said cord so that itdepends behind said wiring without. interfering with said wiring, andsupport means for adapting said cord to be drawn through said openingfor connection to any of the jacks insaid bank, the arrangement of saidswitchboard being designed to provide the essential operating elements,namely the teletypewriter, the jack field and the cord, in the samevertical tier so as to dispense with the usual plug-shelf projecting infront of said switchboard and thereby increase the number of jackswithin reach of an operator seated before said teletypewriter.

13. In a manual cord operated teletypewriter switchboard, an arrangementof elements adapted to increase the number of jacks within reach of, anoperator seated before a teletypewriter in said board, said arrangementcomprising, in combination, a vertical jack field, wiring connected tothe rear of jacks in said field, a teletypewriter, said teletypewriterbeing higher in the rear than in front, means for mounting saidteletypwriter so that its higher rear portion is depressed with respectto its front portion, the rear of said teletypewriter projects behindsaid jack field and the top of said teletypewriter is immediately belowsaid field, an opening in said field dividing said field into separatevertical sections one above the other, means for positioning the levelof said opening between said sections, a horizontal cord shelf in rearof said field and said wiring, means for positioning th level of saidshelf to correspond to the level of said opening, a plug endedcommunications switching cord having one end attached to said shelf,said cord having slack depending behind said teletypewriter and behindsaid wiring, and means for adapting said cord to be drawn through saidopening for connection to any of said jacks in said jack field withoutmechanical interference between either said teletypewriter or saidwiring and said cord.

14. A teletypewriter switchboard arranged to reduce the physical effortof operation and increase the jacks within reach of an operator seatedbefore the teletypewriter by eliminating the usual plug-shelf projectingin front of the switchboard, said switchboard comprising, incombination, a teletypewriter, a teletypewriter support forming part ofand integral with said switchboard, a vertical jack field, wiringconnected to the rear of jacks in said field and a communications cord,said teletypewriter being mounted on said support so that the top ofsaid teletypewriter abuts against the bottom of said jack field, and therear of said teletypewriter projects behind said jack field and isdepressed below the front of said teletypewriter, an opening in saidjack field in vertical alignment with said teletypewriter,

slack in said cord dependingbehind said wiring and said teletypewriter,said cord being arranged to be drawn through said opening for connectionto the front of said jacks, and means for restoring said slack to itsoriginal position without interfering with aid wiring or saidteletypewriter;

15. In a teletypewriter switchboard, in combination, a verticalalignment of operating equipment comprising in vertical sequence fromtop to bottom a first bank of wired jacks, a plugended cord, a secondbank of wired jacks and a teletypewriter, supports for said banks ofjacks, said cord and said teletypewriter in said switchboard said cordbeing arranged so that slack therein may be drawn from the rear of saidbanks through a space separating said banks, and means comprising saidsupports in said switchboard for preventing interference between saidcord and said wiring of said jacks or said teletypewriter inestablishing circuits interconnecting said teletypewriter and said jacksthrough said cord.

16. In a teletypewriter switchboard, in combination, a vertical jackbank, an opening in said bank dividing said bank into two separateportions one above the other, wiring connected to the rear of the jacksin said bank, a teletypewriter projecting into the space immediatelybelow said wiring, a cord, said cord having a first end connected to aswitching plug and a second end connected to a cord-shelf in rear ofsaid bank and said wiring, support means for said cord in rear of saidwiring to adapt said cord to pass through said opening, slack in saidcord between said support and said shelf, said slack passing'through adisplaceable cord weight depending in rear of said wiring and saidteletypewriter, and means for preventing said weight from interferingwith said teletypewriter and said wiring when said cord and weight aredisplaced as said cord is moved through said opening in establishingcircuits interconnecting said teletypewriter and said jacks through saidcord.

1'7. In a teletypewriter switchboard, in combination, a vertical jackfield separated into two parts one above the other by a verticalopening, wiring connected to the rear of jacks in said field, anotheropening immediately below said field and extending behind said field, ateletypewriter having its rear end depressed below its front end andprojecting into said other opening, a support for said teletypewriter insaid other opening, cords passing through displaceable cord weightsdepending behind aid wiring and said teletypewriter, a support for saidcords in said vertical opening, and means for preventing mechanicalinterference between said cord weights and said teletypewriter and saidcord weights and said wiring as said cord weight is displaced as saidcord is drawn through said vertical opening in establishing circuitsinterconnecting said teletypewriter and said jacks through said cord.

PAUL V. KOOS.

